1. Field of the Invention
The present invention relates to a photographic printing apparatus including a transporting section for cutting photosensitive material drawn from one of a plurality of magazines each accommodating therein an elongate photosensitive material into a print size piece and then feeding this material piece into an exposing unit, an order executing means for effecting exposure of image data at the exposing unit on the material piece transported by the transporting section and a calibration printing means for effecting exposure of predetermined calibration data at the exposing unit on the material piece transported by the transporting section.
2. Description of the Related Art
As a technique relating to the photographic printing apparatus having the above-described construction, there is a lab system known from Japanese Patent Application “Kokai” No. 2000-241893.
This lab system includes a polygon mirror for reflecting beams from R, G, B laser sources and a laser exposing section for exposing a print paper (an example of “photosensitive material”) by beams guided by an fθ lens from the sources.
This lab system further includes two magazines for respectively feeding print paper to the laser exposing section, a density determining section for determining an image density of the print paper recording a calibration pattern thereon, a storing means for storing data relating to e.g. the kinds of the print papers stored within the two magazines, lookup tables, etc. and a main controller for controlling these components.
The main controller is operable to execute exposure of the print paper with outputting medium information (a magazine ID, kind of print paper, etc.) and outputting condition information (e.g. the date, temperature, etc. at the time of the output) by the exposure at the laser exposing section.
With the above-described construction, this lab system is capable of calibration of its lookup table for each magazine by charging the print paper after its exposure and development into the density determining section and then determining an image density thereof.
In the case of the photographic printing apparatus having a plurality of magazines, as described in the patent document described above, management of exposure density is needed for each type of photosensitive material. In addition, there is also needed adjustment of an exposure position of image data to be exposed on each photosensitive material.
More particularly, with this type of photographic printing apparatus, the photosensitive material from each magazine is transported as being clamped by plural rollers to the exposing unit or the material from the magazine is guided to the exposing unit by means of a rail-like guide member which contacts the width-wise opposed edges of the material.
Also, with this type of photographic printing apparatus, each magazine and each transporting passage (lane) associated therewith are fixedly set in position relative to each other such that the width-wise center of the material from the magazine may be aligned with the center of the predetermined transporting passage.
With the above apparatus and even with a further apparatus including a plurality of guide passages corresponding to the respective magazines and a subsequent combined guide passage for confluently guiding the materials to the exposing unit, even with proper setting of the magazines, if there exists even a slight error (or tolerance) in the relative positional relations between the guide passages, the center position of the exposure at the exposing unit in the main scanning direction can sometimes be displaced to either direction from the center portion in the main scanning direction of the photosensitive material.
Further, since there exist slight dimensional tolerances in the individual magazines, even if the photosensitive material is appropriately accommodated in the form of a roll within the magazine, the center position in the main scanning direction of the image data formed on the photosensitive material by the exposure at the exposing unit can sometimes be displaced to either side from the center position in the main scanning direction of the photosensitive material.
Occurrence of such displacement (displacement or error in the exposing position) was known in the art. Hence, to cope with this problem, in the case of the conventional photographic printing apparatus, a test printing operation of image data which allows discrimination of the center position of the data in the main scanning direction is effected for each magazine. Then, based on the result of this test printing, adjustment of the exposing position of image data for each magazine is effected. Hence, this process was troublesome. Especially, in the case of a photographic printing apparatus having three or more magazines, the test printing operations for these respective magazines was labor and time consuming. Hence, there has been a desire from the industry for improvement in this respect.